I need help identifying this plant. This is a common low-growing weed (?) in...
I need help identifying this plant. This is a common low-growing weed (?) in our backyard. It grows on the lawn and in garden beds. Prefers partial sun to partial shade, shallow roots (no runners that I can see), and easy to pull up by hand. Often grows in clumps. Grows up to 1.5 feet tall. Leaves are elongated and dark green, 1.5-2 inches long. Flowers are a striking pink-purple, with most blooms in late September to mid-October.
Your weed is Polygonum pennsylvanicum, commonly known as 'smartweed' or 'knotweed'.